Solomon paul davis



(N0 Model.)

s. P. DAVIS.

LIFTING JACK.

No. 337,484. Patented Mar. 9, 1886.

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Nrren STATES PATENT Erica.

SOLOMON PAUL DAVIS OF NAPA, CALIFORNIA.

,LlFTlNG-JACK.

SPECIFICATION forming part of Letters Patent No. 337,484, dated March 9, 1886.

Application filed July 17, 1 885. Serial No. 171,909. (No model.)

To aZZ whom it may concern.-

Be it known that I, SoLoMoN PAUL DAvIs, a resident of the city and county of Napa, State of California, haveinvented a novel and useful Lifting-Jack; and I hereby declare that the following is a full, clear, and exact description of the same, reference being had to the accompanying drawings.

My invention relates to the construction of a device having an adjustable friction-grip on a smooth surface, for lifting vehicles and-other purposes. I

The following description fully explains the nature of my said invention and the manner in which I proceed to construct, apply, and operate the same, the accompanying drawings being referred to by figures and letters.

Figure 1 represents elevation of the jack, with a part in section. Fig. 2 represents an end elevation view of the jack. Fig. 3 represents a plan section through the line A B. Fig. 4 gives two enlarged views of the upper lifting-catch. Fig. 5 gives two views of the lower check-catch.

The frame of my lifting-jack consists of a standard, a, and base I), and may be constructed of either wood or metal, and mortised or cast together. In the upper part of the standard a slot, 0, is cut through its edge for the' insertion of a lex er, (1, with a curved head, which works on a fulcrum-pin, e, and the lifting and check catches, and there is a recess on the edge of the standard for both catches.

Near the top of the standard, and also at a point belowthe recess, are guides it, each having a square slotted head and a shank, which passes through the edge of the standard and is held by a nut or washer; or, if the standard is made of metal, the guides may be cast with it.

A steel lifting catch, f, having a square slotted head and a curved tail corresponding to the curved form of the lever-head, Fig. 4, is inserted in the slot above the supportingpins 9. Below this catch there is inserted also in the slot a steel check-catch, h, having a similarhead, and a tail curving directly from the head and broadening near the end, and working one fulcrum-pin, i, Fig. 5. A lifting-bar, ja square bar of iron having a shoulder tapering on its under sidepasses through the slots in the guides and catches to the base, Fig. 1. A foot of like form to the shoulder inverted may be attached to the lifting-bar.

In its operation in lifting a vehicle the shoulder of the lifting-bar j is placed under the axle and the lever is raised and lowered, each downstrokelifting the vehicle and about half a dozen lifting it several inches. The head of each catch hangs at an incline, Fig. 1, and grips the lifting-bar at a certain angle. The lifting-catch f, having its curved tail resting and working on the curved head of the lever, raises the lifting-bar and retains its grip thereon during the downstroke of the lever; but at the instant of the upstroke it releases the bar and falls on its supportingpins 9. At the downstroke the head of the check-catch h, having its curved tail resting on the fulcrum-pin i, is raised to a level; but at the instant of the upstroke, as the liftingcatch releases its grip on the lifting-bar, the

check-catch falls at an angle and grips the jaw, and holds the entire lift made by the lifting catch. Each catch works independent of the other, and while f responds to the action of the lever and lifts the bar, h holds the bar in a tight grip and retains the gain of each lift by the powerful friction ofits inclined edges against the Smooth surface of the lifting-bar.

The guides It serve to keep the lifting-bar perpendicular and to meet any strain from that line.

In case of wear or breakage, the catches, which are held by neither bolt, pin, nor hook, but are only kept in place by the lifting -bar, which passes through their slot-ted heads, may be removed and new ones replaced readily.

Having thus fully described my invention,

what I claim, and desire to secure by Letters Patent, is-

The combination, in a lifting-jack, of the adjustable liftingcatch fand check catch h, as formed for lifting and gripping a smooth surface, and each being provided with the curved extension or tail described, the lifting-bar j and its guides k, the supportingpinsgfor the lifting-catch, the lever d, as formed and its action on the lifting-catch, and the frame consisting of a standard, at, having a slot, 0, and

the base 11', substantially as described, and for the purposes set forth.

SOLOMON PAUL DAVIS. [n s] Witnesses:

A. B. SMITH, FERDINAND IMHoRsT.

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